The Age Old Question: Do Fish Sleep?

Do fish sleep? A question that you many have pondered at one time or another, but rarely find an answer to. Lo and behold, fish DO sleep, and some have a very interesting way of doing so. Sleeping at night on a coral reef can be a dangerous thing. Any predator can swim by and eat an unsuspecting fish while they are in the vulnerable state of sleep.

However, some crafty reef fish have adapted ways to rest without fear of being eaten. For example, the clever parrotfish will, as night falls, secrete a mucus cocoon around their whole bodies. This cocoon doesn’t taste very good to predators, so the parrotfish can sleep peacefully through the night. Other types of reef fish, such as wrasses, have determined that burying in the sand is the safest way to sleep on a reef full of predators lying in wait. Some fish and other reef creatures are nocturnal, which means they actually sleep during the day and come out only at night.

Survival on the reef can be tough, but if a fish can outsmart its predators, it gets to see another day (or night). Check out our many species of parrotfish, wrasses, and nocturnal reef creatures during your next visit to Coral World!